ha_int_ac97.s

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;**************************************************************
;//file name :HA_int_gpt.s
;//description:
;//modify history
;
;**************************************************************

;**************************************************************
;* the int_handler_entrance
;*			
;*			restore the reg used in the irq modle
;*			chang the modle to the sys modle 
;*			
;*			save the spsr and lr to the sys sp
;*			__________________________________________one layer
;*			save the reg used in the int_handler  ;useless
;*			ent int
;*			open the irq
;*			jump to the int_handler
;*			close irq
;*			jump to the end_int
;* ENTTRANCE OF INT HANDLER
;**************************************************************

	AREA INT_GPT, CODE, READONLY                                                     
	       ENTRY                           ; Mark first instruction to execute 
	       
	include hardware_gfd.h

	       
	       
ENT_INT_DMA 
	
	EXPORT  ENT_INT_DMA
	IMPORT	LR_IRQ
	IMPORT	SPSR_IRQ	
	LDR		RTA, =LR_IRQ   		;load the LR
	LDR		RTA, [RTA]
	sub		RTA,RTA,#4
	stmfd	sp!, {RTA}			;save the LR_IRQ-4 TO the SP_SYS

	LDR		RTA, =SPSR_IRQ
	LDR		RTA, [RTA]
	stmfd	sp!, {RTA}			;save the SPSR_IRQ to the SP_SYS   ;stmfd sp!, {spsr, lr}

	ldr		RTA, =INTC_PLV  		;read the plv  and store in the stack
	ldr		RTA, [RTA]  
	stmfd	sp!, {RTA}        		;save the PLV to the SVC stack

	ldr		RTA, =INTC_PLV		;set the plv
	mov		RTB, #5
	str		RTB,  [RTA]
	
	;jump to the int_handler
	IMPORT	ac97_handler
	bl  		ac97_handler
	
	mrs		RTA, cpsr			;close the IRQ
	orr		RTA, RTA, #0X80   
	msr		cpsr_c, RTA
	IMPORT	END_INT
	b		END_INT
		;=========================================END OF ENT_INT_RTC
	END